problem.halfway printing, extruder change position

Hallo all,

First sorry for my bad. English.

I make a Mendel with Gen3 elektroniks and pololu stepper controllers, and use Repstrapper software.

My problem is: If i print a part the first 15 layers or so, Its go super good, but after the extruder take a other (X Y) position and continues the print.
I tray with a other part that have more then 30 layers and every thing go good.

So one part have problems and a other part (with te same height) go wrong

I load a STL file in to Repsnapper, i dont use steinforce ( i dont now how to use steinforce yet).
Will it be a setting wrong in Repsnapper?

Please help

Gr nonaak

---

First Gen Mendel made by Adrian Bowyer
Controller: RAMPS 1.4
Extruder: Greg's Wade Universal Accessible Extruder
Firmware :Marlin
----------------
MendelMax extra groot
RAMPS 1.4 grafisch display (diy)
Marlin
E3D v6
220V hotbed (diy)

Lang niks in 3Dprinting gedaan, begin nu weer hobby op te pakken.
Weer begonnen met:

Prusa Graber i3 "wood"
RAMPS 1.4 (mks tft28 v1.2 smart touch)
Marlin
E3D extruder v6 lite

If the tool path display in repsnapper looks good, then you might be missing steps in the x and y stepper motors.

thanks for the replay.

its not that, i ingrase the current of the pololu stepper driver. And have the same problem.

Gr nonaak

---

First Gen Mendel made by Adrian Bowyer
Controller: RAMPS 1.4
Extruder: Greg's Wade Universal Accessible Extruder
Firmware :Marlin
----------------
MendelMax extra groot
RAMPS 1.4 grafisch display (diy)
Marlin
E3D v6
220V hotbed (diy)

Lang niks in 3Dprinting gedaan, begin nu weer hobby op te pakken.
Weer begonnen met:

Prusa Graber i3 "wood"
RAMPS 1.4 (mks tft28 v1.2 smart touch)
Marlin
E3D extruder v6 lite

Is your pulley slipping on the motor shaft?

Most likely that the stepper driver is overheating. This may cause you to loose steps. Are you motors hot?